Sage words from Jim, especially if you plan on going out in colder weather.

Me personally, I use an "ultralight" pack that is relatively small in 3 season type conditions. I then switch to a very large pack in cold weather to carry all my bulky insulating stuff in winter. As the difference in weight between my spring->fall pack and my winter pack (the pack itself, not the load in it)is 6 lbs, I'd rather not carry that extra 6 lbs of weight and bulk when I do not need it. (especially when you consider I'm typically carrying a total of about 19->20 pounds on my back for a weekender.)

YMMV, but be sure to ask yourself, "how much does what I'm carrying weigh, and take up in space" "am I carrying extra junk I don't need" and "when am I *realisticly* going to use this pack".

I'll give you both sides of it..

1) Don't fall for the trap of buying an ultralight pack that then isn't comfortable for you with the load you are carrying.

2) Don't fall for the trap of "well I might climb mount everest or go to antarcica or pack in the yukon for 14 days unresupplied" and buy a giant heavy packzilla when all you are doing is going out for 3 seasons with a small amount of gear.

Beware as well that a large pack means you're tempted to take more "extra" stuff. more extra stuff means it's heavier, and you're not as comfortable, and you are then tempted to take more creature comforts. You need enough pack to bring the stuff you have and require for comfort. Not the pack to bring along a vcr, TV, and expresso machine.

The right place for you is the correct place in between those two extremes *for you and your gear*. Which is why we usually reccomend borrowing or renting for the first few trips till you get a good handle on what you really want to carry. It also helps to be able to try it on to see how it fits with the right amount of weight in it. Fit, like in clothing is a very personal thing.